Common problems guide

The most common Ferroli Arena 30 C problems

The faults most likely to send a Ferroli Arena 30 C into lockout — with plain-English causes, what to check first, estimated repair costs and whether you need a Gas Safe engineer.

This model is discontinued. Parts can be harder to source and expensive. If repair costs are mounting, a new A-rated boiler may be the smarter choice.
33 documented codes
6 most common
3 DIY-safe checks
3 engineer needed

The 6 most common faults

01
F 0 5 High DIY-safe

Your boiler has stopped working because the water pressure inside the heating system has dropped too low.

What to try first

Locate the external filling loop, usually a small silver braided hose with one or two valves underneath the boiler.Slowly open the valve(s) to allow water to enter the system while watching the pressure gauge on the front of the boiler.When the needle is between 1 and 1.5 bar, close the valve(s) tightly to stop the flow.

Est. cost
£0-£120
Parts
Filling loop, Pressure relief valve, Pressure sensor
Full guide for F 0 5
02
F37 High DIY-safe

Your boiler has stopped working because the water pressure inside the heating system has dropped too low.

What to try first

Locate the filling loop (a silver flexi hose) under the boiler.Open the valves to allow mains water into the system until the gauge reads between 1.0 and 1.5 bar.Close both valves firmly to stop the flow.

Est. cost
£80-150
Parts
Pressure relief valve, Pressure sensor, Expansion vessel
Full guide for F37
03
F40 High DIY-safe

Your boiler has lost water pressure repeatedly over the last day, which has caused it to stop working to avoid internal damage.

What to try first

Locate the filling loop (a flexible silver hose) underneath your boiler connected to two valves.Open the valves slowly to allow water into the system until the pressure gauge on the front reads between 1.0 and 1.5 bar.Close the valves tightly and check for any visible leaks around radiators or pipework.

Est. cost
£90-180
Parts
Pressure Relief Valve (PRV), Expansion Vessel, Pressure Sensor
Full guide for F40
04
A 0 1 High Engineer

Your boiler has tried to start several times but was unable to light the internal flame.

Est. cost
£120-250
Parts
Ignition electrode, Gas valve, PCB
Full guide for A 0 1
05
A 0 2 High Engineer

Your boiler has detected that it is overheating and has automatically switched itself off to prevent damage.

Est. cost
£120-250
Parts
Overheat thermostat, Pump, PCB
Full guide for A 0 2
06
A 0 4 High Engineer

Your boiler is trying to start, but it cannot successfully ignite or keep the flame burning to heat your water.

Est. cost
£120-250
Parts
Ignition electrode, Gas valve, Flame rectification probe
Full guide for A 0 4
Parts most often replaced

on the Ferroli Arena 30 C

Filling loopPressure relief valvePressure sensorExpansion vesselPressure Relief Valve (PRV)Expansion Vessel

Based on parts cited in our fault code database. Your engineer will confirm what's actually needed after diagnosis.

Call a Gas Safe engineer if…

  • You can smell gas or see signs of a leak
  • The Ferroli shows an Emergency or High severity code
  • The boiler keeps locking out after repeated resets
  • You've tried the DIY checks and the fault hasn't cleared
  • There's visible water leaking from the boiler
  • The flame is yellow or orange instead of blue
See the full 33-code list for the Ferroli Arena 30 C

Related guides

Boiler losing pressure → No hot water → When to replace → Symptom checker →